Using GIS as a Tool for Mitigating Geologic Hazards and Managing Natural Disasters

GIS is a versatile tool that has widespread application before, during, and after catastrophic geologic events. This research project analyzes results from three recently published case studies each corresponding to a point along the crisis response timeline. Planning for various geologic crises is critical, as demonstrated by Tran and others (2009), who utilized GIS to analyze risk factors and map flood hazards in Vietnam. GIS is also an invaluable tool for search and research activities during a natural disaster. These situations require quick response to ensure fast resolution, and GIS can be rapidly deployed through a four step progression in a search and rescue operation (Pfau and Blanford, 2018). In the aftermath of geologic crises, GIS can be deployed to help distribute and coordinate disaster relief efforts. Using Leon County, Florida as a study area, Horner and Downs (2010) used GIS to create a distribution network for relief efforts in the event of a hurricane. While GIS is best known for its widespread use in disaster management planning, it is also an important tool for rapidly responding to emergencies and for organizing post-disaster relief efforts. These studies demonstrate that GIS technologies are highly versatile before, during, and after geologic crisis events. As such, GIS should be viewed as an important strategy in geologic crisis hazard management

Translocation of the temporalis muscle for treatment of facial paralysis

Our purpose was to characterize in the rhesus monkey the structure and function of vascularized temporalis muscle flaps innervated by the facial nerve after translocation into the site of the denervated zygomaticus muscle. Animals were killed at 28 to 120 days following translocation. Control data were obtained from the contralateral side. Twenty-eight days after translocation, the time to reach peak twitch tension and one-half relaxation time were 170% of control zygomaticus muscle. Contraction times decreased with time and reached control values by 100 days. Absolute isometric tetanic tension was not different between the flap (4.29 ± 1.28 newtons; X ± SEM) and control zygomaticus (3.95 ± 0.80 newtons). Succinate oxidase activity of the flap decreased from 279 ± 18 nl O 2 /mg protein/min to control zygomaticus values (98 ± 18) by 110 days. The type 1 fiber cross-sectional area of the flap was 52% of control temporalis muscle and 150% of control zygomaticus muscle ( P < 0.05). The temporalis flap demonstrated viable structure and function and appeared useful in facial movements.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50131/1/880050704_ftp.pd

Comparison of symptomatic and asymptomatic atherosclerotic carotid plaques using parallel imaging and 3 T black-blood in vivo CMR

Background: To determine if black-blood 3 T cardiovascular magnetic resonance (bb-CMR) can depict differences between symptomatic and asymptomatic carotid atherosclerotic plaques in acute ischemic stroke patients. Methods: In this prospective monocentric observational study 34 patients (24 males; 70 +/- 9.3 years) with symptomatic carotid disease defined as ischemic brain lesions in one internal carotid artery territory on diffusion weighted images underwent a carotid bb-CMR at 3 T with fat-saturated pre- and post-contrast T1w-, PDw-, T2w- and TOF images using surface coils and Parallel Imaging techniques (PAT factor = 2) within 10 days after symptom onset. All patients underwent extensive clinical workup (lab, brain MR, duplex sonography, 24-hour ECG, transesophageal echocardiography) to exclude other causes of ischemic stroke. Prevalence of American Heart Association lesion type VI (AHA-LT6), status of the fibrous cap, presence of hemorrhage/thrombus and area measurements of calcification, necrotic core and hemorrhage were determined in both carotid arteries in consensus by two reviewers who were blinded to clinical information. McNemar and Wilcoxon's signed rank tests were use for statistical comparison. A p-value <0.05 was considered statistically significant. Results: Symptomatic plaques showed a higher prevalence of AHA-LT6 (67.7% vs. 11.8%; p < 0.001; odds ratio = 12.5), ruptured fibrous caps (44.1% vs. 2.9%; p < 0.001; odds ratio = 15.0), juxtaluminal thrombus (26.5 vs. 0%; < 0.01; odds ratio = 7.3) and intraplaque hemorrhage (58.6% vs. 11.8%; p = 0.01; odds ratio = 3.8). Necrotic core and hemorrhage areas were greater in symptomatic plaques (14.1 mm(2) vs. 5.5 mm(2) and 13.6 mm(2) vs. 5.3 mm(2); p < 0.01, respectively). Conclusion: 3 T bb-CMR is able to differentiate between symptomatic and asymptomatic carotid plaques, demonstrating the potential of bb-CMR to differentiate between stable and vulnerable lesions and ultimately to identify patients with low versus high risk for cardiovascular complications. Best predictors of the symptomatic side were a ruptured fibrous cap, AHA-LT 6, juxtaluminal hemorrhage/thrombus, and intraplaque hemorrhage

Experimental investigation of muscular neurotization in the rat

Reinnervation of a free muscle graft by nerves from an adjacent intact muscle is called muscular neurotization. This paper investigates the mechanisms and stimuli responsible for muscular neurotization in the rat. Sternohyoid or sternomastoid muscles were transplanted as free muscle grafts to the ventral surface of an intact sternohyoid muscle (feeder muscle). After several weeks the graft and underlying feeder muscle were removed together, frozen, serially sectioned, stained, and carefully examined for the presence or absence of nerves. It was concluded from a series of experiments that in this model muscular neurotization is a form of nerve regeneration. In order for muscular neurotization to occur, it is necessary to have (1) injury to the nerves of the intact feeder muscle and (2) a pathway upon which the regenerating nerves may grow into the graft.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50139/1/880100607_ftp.pd

Short-term duration of load and cyclic performance of metal-plate-connected truss joints

The objective of this research was to evaluate the duration of load factor for metal-plate-connected (MPC) truss joints subjected to various cyclic loading conditions. Heel and tension-splice joints from a standard 30-foot span Fink truss constructed from nominal 2x4 Douglas-fir lumber were tested. A testing frame similar to that developed by Gupta and Gebremedhin (1990) was used to test the joints under several different loading conditions. A static ramp load of 780 lbs./min. was applied to ten joints (both tension-splice and heel joints) until failure was reached. This test group served as the control group for comparison with joints tested under several cyclic loading regimes, with ten joints (per joint type) in each sample group. At the end of these cyclic loadings, the joints were ramped to failure (if they survived the cyclic loading). Results were evaluated by comparing the ultimate loads and stiffnesses from the control group specimens to those from the cyclic loading groups. An evaluation of the damage resulting from the cyclic loads is also discussed. Reductions in the stiffness and strength of the joint after the cyclic loading are related to the number of cycles, and the amplitude of the cycles. The results of this research show that the current duration of load factor of 1.6 for earthquake loading used in the design of MPC joints is adequate